Regeneration treatment method of waste shell-mold and system thereof

Abstract

A regeneration treatment method of waste shell-mold and a system thereof are provided. The regeneration treatment method has a raw smashing step, a smashed-particle sieving step smashed-particle, a first magnetic separation step, a grinding step, a second magnetic separation step, a dry pneumatic flotation step, and a vibration sieving step in sequence to obtain a regenerated shell-mold sand. The refined shell-mold sand is obtained from the smashed-particle sieving step. Silica binders of the refined shell-mold sand is effectively removed by the grinding step. Furthermore, particle sizes of the regenerated shell-mold sand fall in a suitable range in the grinding step. Magnetic metals mixed in the waste shell-mold are effectively removed by the first and second magnetic separation steps. Non-magnetic impurity are further removed by the dry pneumatic flotation step. Therefore, the regenerated shell-mold sand are suitable to substitute original shell-mold sand.

What is claimed is: 
     
         1 . A regeneration treatment method of waste shell-mold comprising steps of:
 (a) raw smashing waste shell-molds into raw shell-mold sand;   (b) sifting out refined shell-mold sand from the raw shell-mold sand, wherein particle sizes of the refined shell-mold sand fall within a first particle size range;   (c) removing magnetic metal particles mixed in the refined shell-mold sand;   (d) whirling and grinding the refined shell-mold sand by colliding with each other to remove silica binders adhered to surfaces of the refined shell-mold sand to obtain a shell-mold sand granular material;   (e) removing magnetic metal powders mixed in the shell-mold sand granular material;   (f) removing non-magnetic impurity mixed in the shell-mold sand granular material during the shell-mold sand granular material being blown by an airflow to separate regenerated shell-mold sand from the shell-mold sand granular material; and   (g) rolling the regenerated shell-mold sand on a metal sieve to remove dust adsorbed on the regenerated shell-mold sand by the static electricity and to collect the regenerated shell-mold sand remaining on the metal sieve.   
     
     
         2 . The regeneration treatment method of waste shell-mold as claimed in  claim 1 , wherein the step (d) comprises a plurality of grinding procedures. 
     
     
         3 . The regeneration treatment method of waste shell-mold as claimed in  claim 2 , wherein in the step (f):
 the non-magnetic impurity comprises non-magnetic impurity particles and non-magnetic impurity powders;   a density of the non-magnetic impurity particles is greater than a density of the regenerated shell-mold sand;   particle sizes of the non-magnetic impurity powders are less than particles sizes of the regenerated shell-mold sand; and   when the airflow blows upward, the regenerated shell-mold sand is floated and the non-magnetic impurity powders are blown away by the airflow.   
     
     
         4 . The regeneration treatment method of waste shell-mold as claimed in  claim 2 , wherein in the step (f), the airflow is an oblique airflow and the shell-mold sand granular material is moved horizontally by the oblique airflow. 
     
     
         5 . The regeneration treatment method of waste shell-mold as claimed in  claim 1 , wherein in the step (f), the airflow is an oblique airflow and the shell-mold sand granular material is moved horizontally by the oblique airflow. 
     
     
         6 . The regeneration treatment method of waste shell-mold as claimed in  claim 4 , wherein
 the step (g) comprises a plurality of vibration sieving procedures; and   the vibration sieving procedures use a plurality of metal sieves with different mesh sizes, and the mesh sizes of the metal sieves are arranged from large to small according to the order in which the vibration sieving procedures are carried out.   
     
     
         7 . The regeneration treatment method of waste shell-mold as claimed in  claim 6 , wherein the step (g) comprises four vibration sieving procedures and the mesh sizes of the metal sieves decrease according to the first vibration procedure to the fourth vibration procedure, wherein:
 the first vibration sieving procedure collects the regenerated shell-mold sand having the particle sizes that fall within a second particle size range; wherein the second particle size range is between the mesh size of the metal sieve applied in the first vibration sieving procedure and a maximum of the first particle size range;   the second vibration sieving procedure collects the regenerated shell-mold sand having the particle sizes that fall within a third particle size range; wherein the third particle size range is between the mesh size of the metal sieve applied in the second vibration sieving procedure and the mesh size of the metal sieve applied in the first vibration sieving procedure;   the third vibration sieving procedure collects the regenerated shell-mold sand having the particle sizes that fall within a fourth particle size range; wherein the fourth particle size range is between the mesh size of the metal sieve applied in the third vibration sieving procedure and the mesh size of the metal sieve applied in the second vibration sieving procedure; and   the fourth vibration sieving procedure collects the regenerated shell-mold sand having the particle sizes that fall within a fifth particle size range; wherein the third particle size range is between the mesh size of the metal sieve applied in the fourth vibration sieving procedure and the mesh size of the metal sieve applied in the third vibration sieving procedure.   
     
     
         8 . The regeneration treatment method of waste shell-mold as claimed in  claim 1 , wherein the first particle size range is between 4 mm to 6 mm. 
     
     
         9 . A regeneration treatment system of waste shell-mold comprising:
 a smasher for smashing waste shell-molds into raw shell-mold sand;   a sieving machine connected to the smasher for receiving the raw shell-mold sand obtained from the smasher and for sifting out refined shell-mold sand from the raw shell-mold sand; wherein particle sizes of the refined shell-mold sand fall within a first particle size range;   a first magnetic separator connected to the sieving machine for receiving the refined shell-mold sand sifted out by the sieving machine and for removing magnetic metal particles mixed in the refined shell-mold sand;   a grinder connected to the first magnetic separator, comprising at least one grinding chamber for receiving and whirling the refined shell-mold sand, wherein the refined shell-mold sand are ground by colliding to each other in the at least one grinding chamber to remove silica binders adhered to surfaces of the refined shell-mold sand and to obtain a shell-mold sand granular material;   a second magnetic separator connected to the grinder for receiving the shell-mold sand granular material and for removing magnetic metal powders mixed in the shell-mold sand granular material;   a dry pneumatic flotation machine connected to the second magnetic separator, comprising a floatation chamber for receiving the shell-mold sand granular material, for removing non-magnetic impurity particles mixed in the shell-mold sand granular material, and for blowing away non-magnetic impurity powders mixed in the shell-mold sand granular material by an airflow in the flotation chamber to obtain regenerated shell-mold sand; and   a rotary vibration sieving machine connected to the dry pneumatic flotation machine, comprising a metal sieve for receiving the regenerated shell-mold sand, and for rolling the regenerated shell-mold sand on the metal sieve to remove dust adsorbed on the regenerated shell-mold sand by the static electricity and to collect the regenerated shell-mold sand remaining on the metal sieve.   
     
     
         10 . The regeneration treatment system of waste shell-mold as claimed in  claim 9 , wherein the smasher is a drum type smasher having a smashing drum comprises:
 a waste shell-mold inlet designed for the waste shell-molds to be fed into the smashing drum; and   a raw shell-mold sand outlet designed for the raw shell-mold sand to leave the smashing drum; wherein a direction of an opening of the waste shell-mold inlet and a direction of an opening of the raw shell-mold sand outlet are vertical to each other.   
     
     
         11 . The regeneration treatment system of waste shell-mold as claimed in  claim 10 , wherein the rotary vibration sieving machine further comprises:
 a framework;   a vibration unit mounted on and connected to an outer side of the framework; and   at least one sieve frame mounted obliquely in the framework and comprising a plurality of metal sieves having the same mesh size and a regenerated shell-mold sand outlet mounted on the lowest side of the at least one sieve frame.   
     
     
         12 . The regeneration treatment system of waste shell-mold as claimed in  claim 9 , wherein the sieving machine has a perforated sieve plate. 
     
     
         13 . The regeneration treatment system of waste shell-mold as claimed in  claim 9 , wherein the grinder further comprises:
 a shell;   a bottom plate mounted in the shell, defining the at least one grinding chamber with the shell, and having a plurality of airflow outlet pipes mounted vertically on the bottom plate;   a refined shell-mold sand inlet mounted on the shell, communicating with the at least one grinding chamber, and designed for the refined shell-mold sand separated from the first magnetic separator to be fed into the at least one grinding chamber;   a shell-mold sand granular material outlet mounted on the shell, communicating with the at least one grinding chamber for the shell-mold sand granular material to leave the at least one grinding chamber;   at least one roller mounted in the corresponding at least one grinding chamber; wherein a distance is kept between the at least one roller and the corresponding airflow outlet tubes of the bottom plate; and   at least one driving apparatus mounted on a side of the shell and connecting to the corresponding at least one roller to drive the corresponding at least one roller to rotate.   
     
     
         14 . The regeneration treatment system of waste shell-mold as claimed in  claim 13 , wherein:
 an airflow chamber is defined in the shell; wherein the bottom plate separates the airflow chamber and the at least one grinding chamber, and the airflow outlet tubes communicate the at least one grinding chamber with the airflow chamber; and   the shell has an airflow inlet disposed on a middle segment of the shell corresponding to the airflow chamber.   
     
     
         15 . The regeneration treatment system of waste shell-mold as claimed in  claim 14 , wherein:
 the grinder further comprises three partitions arranged separately from each other and mounted vertically on the bottom plate to define a first grinding chamber, a second grinding chamber, a third grinding chamber and a fourth grinding chamber with the shell and the bottom plate; wherein each partition has an oblique channel and the oblique channels communicate the first to fourth grinding chambers with each other;   the refined shell-mold sand inlet communicates with the first grinding chamber;   the shell-mold sand granular material outlet communicates with the fourth grinding chamber;   an amount of the at least one roller is four, and the four rollers are respectively mounted in the first grinding chamber to the fourth grinding chamber; and   an amount of the at least one driving apparatus is four, and the four driving apparatuses are respectively connected to the four rollers.   
     
     
         16 . The regeneration treatment system of waste shell-mold as claimed in  claim 9 , wherein the dry pneumatic flotation machine further comprises:
 a housing comprising a shell-mold sand granular material inlet and a regenerated shell-mold sand outlet respectively mounted on two opposite sides of the housing; wherein the shell-mold sand granular material separated from the second magnetic separator is fed into the flotation chamber through the shell-mold sand granular material inlet and the regenerated shell-mold sand leaves the flotation chamber through the regenerated shell-mold sand outlet;   a bottom board mounted in the housing, located at a lower side of the shell-mold sand granular material inlet and the regenerated shell-mold sand outlet, and having a plurality of oblique air outlet tubes spaced with each other, extending from the bottom board to the flotation chamber, and inclining toward the outlet of the housing from the bottom board;   the bottom board defines the flotation chamber with the housing; and   the shell-mold sand granular material inlet and the regenerated shell-mold sand outlet communicate with the flotation chamber.   
     
     
         17 . The regeneration treatment system of waste shell-mold as claimed in  claim 16 , wherein:
 an airflow chamber is defined in the housing; wherein the bottom board separates the airflow chamber and the flotation chamber, and the oblique air outlet tubes communicate the flotation chamber with the airflow chamber; and   the housing of the dry pneumatic flotation machine comprises:   an airflow inlet disposed on a middle segment of the housing corresponding to the air chamber; and   a powder collector disposed on the housing and communicating with the flotation chamber.   
     
     
         18 . The regeneration treatment system of waste shell-mold as claimed in  claim 9 , wherein the rotary vibration sieving machine further comprises:
 a framework;   a vibration unit mounted on and connected to an outer side of the framework; and   at least one sieve frame mounted obliquely in the framework and comprising a plurality of metal sieves having the same mesh size and a regenerated shell-mold sand outlet mounted on the lowest side of the at least one sieve frame.   
     
     
         19 . The regeneration treatment system of waste shell-mold as claimed in  claim 18 , wherein:
 an amount of the at least one sieve frame is four; wherein first to fourth sieve frames are mounted in the framework from upside to downside and the first to the fourth sieve frames tilt from a side close to the vibration unit to another side away from the vibration unit;   the first to the third sieve frames respectively have an inclined hopper;   the inclined hoppers are respectively mounted on a downside of the corresponding first to third sieve frames and the metal sieve thereof;   the inclined hoppers inclining from a side far from the vibration unit to another side close to the vibration unit, and has an opening formed on the side close to the vibration unit; and   the mesh sizes of the metal sieves respectively mounted on the first to the fourth sieve frames decrease according to the order of the first to fourth sieve frames.   
     
     
         20 . The regeneration treatment system of waste shell-mold as claimed in  claim 9 , wherein
 the first magnetic separator has an electromagnetic mounted therein; and   the second magnetic separator has an electromagnetic mounted therein.